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DEPARTMENT OF THE INTERIOR 

UNITED STATES GEOLOGICAL SURVEY 

GEORGE OTIS SMITH, Director 



Bulletin 592—1 


THE CHISANA PLACER DISTRICT 

ALASKA 


BY 


ALFRED H. BROOKS 


Mineral Resources of Alaska, 1913—I 




WASHINGTON 

GOVERNMENT PRINTING OFFICE 

1911 



















































DEPARTMENT OF THE INTERIOR 

UNITED STATES GEOLOGICAL SURVEY 

GEORGE OTIS SMITH, Director 


Bulletin 592—1 


THE CHISANA PLACER DISTRICT 

ALASKA 


BY 

ALFRED H. BROOKS 

ii 


Mineral Resources of Alaska, 1913—I 



WASHINGTON 

GOVERNMENT PRINTING OFFICE 

1914 

r\ * 

I A/ / •"! 






CONTENTS, 


I 

, AlT)7 


Page. 


Introduction. 309 

Geography.'. 310 

Topography. 310 

Drainage. 310 

Climate. 311 

Vegetation. 311 

Game and fish... 311 

Geology. 311 

Sedimentary and volcanic rocks. 311 

Igneous intrusives. 312 

Structure. 312 

Unconsolidated deposits. 313 

Gold deposits. 314 

History of discovery. 314 

Geographic nomenclature. 315 

Placers. 316 

Future of placer mining.1. 317 

Copper. 318 

Means of communication. 319 

Industrial conditions. 320 


ILLUSTRATIONS. 


Page. 

Plate XIII. Sketch map showing mineral deposits of the Nabesna, Chisana, 


and White river basins. 310 

XIV. Sketch map of the Chisana placer district. 316 


0. 0P D, 

17 'm 


II 



























THE CHISANA PLACER DISTRICT. 


By Alfred H. Brooks. 


INTRODUCTION. 

The Chisana placer district, also called the Shushana district, 
comprises an ill-defined area lying in the headwater region of Chisana 
• River (sometimes known as the Shushana), which joins with the 
Nabesna to form the Tanana, which in turn flows into the Yukon. 
The discovery of gold placers in this district in 1913 made it the 
focal point of interest to miners and prospectors and resulted in a 
large influx of people from all parts of Alaska, as well as from out¬ 
side of the Territory. This region has not been visited by any mem¬ 
ber of the Survey since the finding of the placer gold. Its geology 
and topography are, however, fairly well known through previous 
surveys, and much data on the occurrence of the alluvial gold have 
been obtained from several reliable sources. 

While exploring White and Tanana rivers in 1898 W. J. Peters 
and the writer passed about 40 miles north of the locality at which 
gold was discovered, 1 and the following year extended this work by 
an exploration 2 which traversed the headwaters of the Chisana. At 
about the same time Rohn 3 4 reached this region by crossing the 
Wrangell Mountains from the south. More accurate surveys were 
made in the same field in 1902 4 by F. C. Schrader and W. C. Men¬ 
denhall. The most comprehensive report on this province is that by 
Moffit, Knopf,, and Capps, 5 who in 1908 extended the geologic and 
topographic mapping of this area. 

Since the discovery of placer gold the district has also been visited 
by D. D. Cairnes, of the Geological Survey of Canada. Mr. Cairnes 
has kindly furnished the writer both with cartographic data and 
with an advance copy of a paper 6 containing the results of this 

1 Brooks, A. H., A reconnaissance in the White and Tanana river basins, Alaska, in 1898: TJ. S. Geol. 
Survey Twentieth Ann. Rept., pt. 7, pp. 425-494,1900. 

2 Brooks, A. H., A reconnaissance from Pyramid'Harbor to Eagle City, Alaska: U. S. Geol. Survey 
Twenty-first Ann. Rept., pt. 2, pp. 331-391, 1900. 

3 Rohn, Oscar, A reconnaissance of the Chitina River and the Skolai Mountains: U. S. Geol. Survey 
Twenty-first Arm. Rept., pt. 2, pp. 393-440,1900. 

4 Mendenhall, W. C., and Schrader, F. C., The mineral resources of the Mount Wrangell district, Alaska: 

U. S. Geol. Survey Prof. Paper 15,1903. 

& Moffit, F. II., and Knopf, Adolph, Mineral resources of the Nabesna-White River district, Alaska, 
with a section on the Quaternary by S. R. Capps: U. S. Geol. Survey Bull. 417, 1910. 

«Cairnes, D. D., Chisana gold fields: Canadian Min. Inst. Bull. 24,1914. 


54996°—14 


309 






310 


MINERAL RESOURCES OF ALASKA, 1913. 


examination. The writer is also fortunate in haying the use of 
notes made by A. C. Baldwin, engineer of the International Bound¬ 
ary Commission, who passed through the Chisana district in the fall 
of 1913, as well as those of A. Neustaedter, a mining engineer, who 
also recently visited this field. Much information is therefore avail¬ 
able concerning the region in which the discovery was made, and it 
will be summarized here for the use of the prospector. The writer’s 
own field work of many years ago, of course, furnished only a small 
part of the data here presented. 

GEOGRAPHY. 

Topography .—The site of the placer-gold discovery is centrally 
located in the quadrangle roughly blocked out by the international, 
boundary on the east, meridian 143° and parallels 61° 30' and 63°. 
(See PI. XIII.) Its southwestern part is occupied by the snow and 
ice clad Wrangell Mountains, whose highest peaks are over 16,000 
feet above sea level. On the north the Wrangell Mountains fall off 
abruptly to a belt of lesser relief that stretches from White River 
on the southeast to the head of Copper River on the northwest. 
Northeast of this depression are the Nutzotin Mountains, a rugged 
highland area about 20 miles in width, whose peaks stand from 5,000 
to 10,000 feet above sea level. These mountains fall off on the north¬ 
east to the upper Tanana lowland, a gravel-floored plain about 20 
miles in width and about 3,000 feet above sea level. This is bounded 
on the north by the rolling upland of the Yukon-Tanana region. 

To recapitulate, there are in this region five topographic provinces, 
namely, the Wrangell and Nutzotin mountains, a zone of lesser 
relief separating the two, the Tanana lowland, and the Yukon- 
Tanana upland. 

Drainage .—The drainage of the region is carried north and east to 
the Yukon by three large rivers—the White, the Chisana, and the 
Nabesna. The first springs from Russell Glacier, occupying Skolai 
Pass, and maintains an easterly direction for some 30 miles, flowing 
through a broad gravel-filled valley with gentle slope. Near the 
international boundary it enters a steep-walled valley, from which 
it emerges 15 miles below, and thence to the Yukon occupies abroad 
valley. 

The Chisana and Nabesna valleys are of the same topographic 
type. Both rise in glaciers on the northeast flank of Wrangell Moun¬ 
tains. Just below their glacial sources they receive numerous tribu¬ 
taries whose broad valleys form a part of the depression between 
the Wrangell and Nutzotin mountains. Leaving these basins they 
enter the Nutzotin Mountains, which they traverse through narrow 
steep-walled valleys about 20 miles in length and then debouch 
on the Tanana lowland. These rivers maintain a northwesterly 


U. S. GEOLOGICAL SURVEY 


EULLEtIN 592 PLATE Xlll 



X Copper + Lode gold © Placer gold - Trail 

SKETCH MAP SHOWING MINERAL DEPOSITS OF THE NABESNA, CHISANA, AND WHITE 

RIVER BASINS. 
































. > : 


. J* ‘ 



. •••. ■ 




. 




p. 









































THE CHISANA PLACER DISTRICT. 


311 


course across this lowland to the north rim of the valley, where they 
join to form the Tanana. They are gravel floored throughout their 
length and flow with tempestuous current. 

Climate .—The Chisana region lies in the inland climatic province 
of Alaska, which is characterized by semiarid conditions, severe 
winters, and mild, bright summers. In the Wrangell Mountains there 
is a heavy snowfall, but in the region north of this range the aggre¬ 
gate precipitation is small. Less than 2 feet of snow is reported in 
the upper White River basin, and the total precipitation for the year 
is probably less than 10 inches. There are no records, but the rain¬ 
fall in the upper Chisana and Nabesna basins is probably a little 
greater than in other parts of the province. 

Vegetation .—Timber is rather scant in the district. In the valley 
bottoms spruce and other varieties of trees are found, the largest of 
which are 18 to 20 inches in diameter. Timber line is 300 to 500 feet 
above the floors of the main valleys. Above this there is a stunted 
growth of willow, which locally is found 1,000 feet above the limit of 
the spruce. The best timber of the district is in the upper White, 
Chisana, and Nabesna basins and in the Tanana lowland. 

Grass is abundant in many parts of the region. The bars of upper 
White, Chisana, and Nabesna rivers and the Tanana lowland are 
especially noted for their forage plants. Unlike most other parts 
of Alaska, this region furnishes some winter as well as summer pasture. 
Owing to the dry chmate the grass cures on the stalk, and as the light 
snowfall blows away in favored localities, winter grazing is possible. 
Horses have been frequently wintered in the region without feeding. 
It is not known how much of this winter pasturage there is. as only 
local patches have been utilized. 

Game and fish .—While some forms of agriculture are undoubtedly 
possible in this region, so far the only source of food has been the 
game and fish. The large game includes sheep, abundant in the 
mountains; moose, not very plentiful; and caribou, which in some 
years are present in considerable numbers. Large brown bears, 
probably grizzlies, as well as black bears are found in the region, and 
there are many smaller fur-bearing animals. Ptarmigan are seen 
above timber line and grouse in the lowlands. The Tanana flats are 
breeding grounds for geese, ducks, and other water fowl. Salmon do 
not reach the region, but grayling, or arctic trout, are abundant in 
the clear-water streams, and the lakes contain a species of whitefish. 

GEOLOGY. 

Sedimentary arid volcanic rochs .—The oldest rocks of this province 
are phyllites, impure limestones, mica schists, and gneissoid granites 
such as make up the highlands north of the Tanana lowland. The 


312 


MINERAL RESOURCES OF ALASKA, 1913. 


metamorphic series is to be correlated with the Birch Creek schist of 
the Yukon-Tanana region, believed to be of Cambrian or pre- 
Cambrian age. With these are associated some greenstone schists 
that are probably younger than the other crystalline rocks. 

Overlying these are heavy conglomerates and slates that are 
probably of Devonian age. These rocks were found in a series of 
isolated hills that rise out of the gravel flat connecting the upper 
Tanana lowland with the middle White River valley. The north 
front of the Wrangell Mountains is made up of slates, volcanic rocks, 
and massive limestones that contain Carboniferous fossils. The rela¬ 
tion of these to the conglomerates and slates (Devonian) above 
described has not been determined, as the two series are 30 or 40 
miles apart. 

A profound fault is believed to separate these Carboniferous rocks 
from the formations that make up the Nutzotin Mountains, which are 
composed of slates and graywackes, with some beds of fine conglomer¬ 
ate and a little limestone. These rocks are of Mesozoic age, probably 
chiefly Lower Cretaceous and Jurassic, but include some Triassic 
limestones and slates. They probably also occur above the Carbonif¬ 
erous on the Wrangell Mountains but have not there been definitely 
recognized. The most abundant Tertiary formation is the great 
complex of lavas that makes up the Wrangell Mountains, whose 
northern margin reaches into the district here discussed. Some 
sandstones have been found in the Tanana Valley below the Nabesna, 
and these are probably Tertiary. These sandstones have not been 
found in the region here discussed, but coal has been found in the 
upper White River basin near the international boundary and is 
probably of Tertiary age; the Tanana lowland may perhaps be carved 
out of rocks of this formation. 

Igneous intrusives. —Igneous intrusives are not uncommon in the 
region. Most of those occurring in the larger masses are dioritic. 
Some are granitic. Rocks that have a general lithologic similarity to 
these but are porphyritic in texture also occur in dikes through¬ 
out much of the region. These intrusives are widely distributed and 
probably belong to one general period of intrusion, which is believed 
to be Mesozoic. In addition to these there are probably older gra¬ 
nitic intrusives, now represented by gneissic rock, in the region lying 
north of the Tanana lowland. Diabase dikes also occur in some parts 
of the area and are probably of Tertiary age. 

Structure. —All the terranes described above have a general north¬ 
west-southeast strike. The metamorphic rocks have been intensely 
squeezed and sheared, their planes of foliation dipping generally to 
the north. It is probable that the structure of the Nutzotin Moun- 


THE CHISANA PLACER DISTRICT. 


313 

tains is synclinal, as older rocks are found both north and south of 
the range. The detailed structure of these mountains is, however, 
complex, and both strikes and dips vary from place to place. It has 
already been noted that the Nutzotin Mountains and Wrangell Moun¬ 
tains are probably separated by a profound fault. On the southwest 
side of this fault the rocks usually dip to southwest, and the evidence 
in hand indicates that the structure of the Wrangell Mountains also 
is synclinal. 

Unconsolidated deposits .—All the larger river valleys are deeply 
filled with silts, sands, and gravels. This blanket of unconsolidated 
material extends in some places far up the hill slopes. On White 
River, for example, it occurs 600 feet above the valley bottom, and 
it is found on the divides between White and Chisana rivers 1,200' 
feet above the valley bottoms. 

Most of the material is directly or indirectly the result of glacial 
action. The larger rivers and many of the small streams head in 
glaciers, which are continually contributing debris that is carried 
away by the streams and deposited below. These glaciers formerly 
extended farther down the valleys than they do now. White River 
valley was once filled with ice far below the international boundary,, 
and the valleys of the Chisana and Nabesna were filled to the northern 
front of the Nutzotin Mountains. Gravels and sands were deposited] 
along the margins of these glaciers, and finer material was deposited in 
front, as outwash deposits, especially during the recession of the ice, 
which was accompanied by flooding of the water courses. In addition 
to these water-laid deposits, ice-borne material also was laid down by 
glaciers and is now found in some localities in the form of bowlder 
clay. Most of the unconsolidated material of the district is therefore 
directly or indirectly of glacial origin. The possibility of finding 
preglacial gravels is considered under the discussion of placers (p. 317). 

A deposit of white tuff that occurs immediately underneath the 
soil is one of the most striking formations of the district. It is found 
in huge drifts in the Copper-White River basin and as a white bed in 
other parts of the area. This is part of an eruption of a volcano 
whose ejecta fell over an area of more than 20,000 square miles in 
the upper Yukon basin. According to Thomas Riggs, jr., engineer 
of the International Boundary Commission, the source of this tuff 
is a small crater near the international boundary, not far from the 
front of St. Elias Range. 

Heavy beds of peat occur in the upper White River basin. In one 
section several beds of peat were observed separated by layers of 
fine sand or silt. 


314 


MINERAL RESOURCES OF ALASKA, 1913 . 
GOLD DEPOSITS. 


History of discovery .—The exploration of the Tanana in 1898 led 
the writer to form the opinion that the metamorphic rocks north of 
the lowland had been mineralized, as indicated by the following 
quotation: 1 

Near the mouth of Scottie Creek, on the Tanana, is an exposure of impure limestone 
schist and mica schist. The rock has been much deformed, and quartz veins are 
numerous. The mineral-bearing solutions have been injected in a zone of shearing 
some 30 feet wide, in which lie numerous mineralized quartz veins. Copper and iron 
pyrite were observed, and probably some galena. In a specimen of the calcareous 
schist taken from close to the shear zone, but not forming part of it, I found some grains 
of gold which had evidently been brought in by the penetrating solution. The gold 
occurs in the unaltered rock and was not associated with any extraneous matter. 

At another locality, about 15 miles below the mouth of the Robertson River, on the 
north side of the Tanana, a mineralized shear zone was found in the granite. This 
zone was not over 10 feet wide, and the granite along it had been brecciated rather 
than deformed. In this zone pyrite was observed and a few fine particles of gold. 

During the hurried traverse of the Nutzotin Mountains made in the 
following year indications of some local auriferous mineralization 
were seen, but no very encouraging evidence of the presence of gold 
was found. It remained for Schrader in 1902 to offer more definite 
proof of the presence of auriferous quartz. His report is quoted as 
follows: 2 

On the Chisana no gold was found above the Nutzotin Mountains. The Mesozoic 
rocks of the Nutzotin Range, however, consisting of slates, schists, greywackes, 
shales, limestones, and conglomerates, beyond doubt contain some gold. In these 
rocks one would expect the quartz, which occurs either as veinlets or stringers along 
the bights of folds or in the crushed material along faults and shear zones, to be the 
most favorable place to look for gold. An assay of a sample of quartz collected in a 
shear zone at the head of the canyon on the west side of the river gave a trace of gold. 
From a similar occurrence of quartz and calcite in crumpled shistose limestone and 
slate on Mound Creek a specimen was collected for assay. The returns gave 0.03 
ounce of gold and a trace of silver, a money value of 60 cents per ton. 

When in 1908 Mofht and Knopf visited the region they found that 
some auriferous quartz veins had been located, and the results of 
their studies are summarized by them as follows: 3 

From the descriptions given in the preceding pages, it will be apparent that a lode- 
quartz region of some promise has been discovered in the Nutzotin Mountains near 
the international boundary and that as yet it has been but imperfectly explored by 
the prospector. It has been shown that the intrusion of quartz diorite produced a 
number of contact-metamorphic bodies of copper sulphides, and the occurrence on . 
Jacksina Creek suggests that the magma was also capable of effecting an auriferous 
mineralization. From the meager data at hand it is perhaps unsafe to venture on 

1 Brooks, A. H., A reconnaissance in the White and Tanana river basins, Alaska, in 1898: U. S. Geol. 
Survey Twentieth Ann. Rept., pt. 7, pp. 486-487, 1900. 

2 Mendenhall, W. C., and Schrader, F. C., The mineral resources of the Mount Wrangell district, Alaska: 

U. S. Geol. Survey Prof. Paper 15, p. 45, 1903. 

3 Moffit, F. II., and Knopf, Adolph, Mineral resources of the Nabesna-White River district, Alaska, 
with a section on the Quaternary by S. R. Capps: U. S. Geol. Survey Bull. 417, p. 62,1910. 



THE CHISANA PLACER DISTRICT. 


315 


generalizations, yet it is probable that the quartz veins are genetically related to the 
intrusion of the post-Carboniferous quartz diorites and that therefore the intruded 
areas are those most likely to be mineral bearing. Such areas are known to occur 
throughout the Nutzotin Mountains at a number of localities, especially along their 
northeastern flanks. Brooks has mapped a large area of granular intrusive on the 
lower Nabesna. It is probable that in the vicinity of such masses the search for lode 
quartz may be prosecuted with the most hope of success. 

Though copper deposits have been known in this district since 1899 
and gold since 1902 neither have been much developed. Assessment 
work has been kept up and some developments have been made on 
both copper and gold lode claims, but the inaccessibility of the region 
has discouraged all but a few miners. Probably not over an average 
of 25 men were in the entire region until the placer gold was discovered. 
Some search was made for gold placers and several prospects were 
found, but there was no productive mining. A number of years 
ago a little sluicing was done near the scene of the recent discovery, 
but without encouraging results. 

William E. James and Peter Nelson are credited with having found 
the first workable placer. This discovery, which took place on May 3, 
1913, was made on a creek called Bonanza by the prospectors, 
but more important was the find made on a small tributary of the 
stream named Little Eldorado. Gold was also found in the gravels 
of other near-by streams, but mining in 1913 was largely confined to 
Little Eldorado. 

Geographic nomenclature .—In accordance with the prevailing 
practice, the prospectors in this district promptly applied new names 
to every watercourse on which claims were staked, giving no heed to 
the fact that 10 years before this influx of miners an official and 
accurate map of the district had been published on which every 
effort had been made to apply the correct Indian nomenclature to 
these streams. These authorized names were entirely ignored by the 
prospectors; Chatenda Creek became Johnson Creek, Chapolda Creek 
became Wilson Creek, and a new crop of Bonanza, Eldorado, Glacier, 
Coarse Gold, and Goldbottom creeks were started—names that have 
been used scores of times and that appear in every placer district 
of Alaska. It is unworthy of Alaska pioneers to substitute this com¬ 
monplace terminology for the euphonious native names, and especially 
to persist in the foolish duplication of geographic place names. 
Concerted effort should be made by Alaskans to put a stop to this 
thoughtless practice, which leads to hopeless confusion. 

Unfortunately these prospectors’ names can not be ignored, for 
they are used in recording claims and thus form a part of the court 
records. Names of the watercourses have been changed by pros¬ 
pectors as follows: Chisana River to Shushana River, GehoendaCreek 
to Trail Creek, Chatenda Creek to Johnson Creek, and Chapolda 


316 


MINERAL RESOURCES OF ALASKA, 1913. 


Creek to Wilson Creek. Other names also have probably been 
changed, but of these there is as yet no record. 

Placers .—Auriferous gravels have been found in an area about 
5 by 8 miles square lying east of and tributary to the upper Chisana 
(Pl. XIV), but from what is known of the geology of the region 
there is no inherent reason why the gold-bearing area should be so 
limited. This area is drained by Chatenda (Johnson) and Chapolda 
(Wilson) creeks. The headwaters of these streams include rather 
broad open basins, but in their lower courses they flow through 
narrow, steep-walled canyons. Only their lower courses are tim¬ 
bered, their upper basins, where the actual mining has been done, 
being far above the limit of timber. 

The bedrock of the district is chiefly closely folded gray and black 
shale with some intercalated beds of sandstone and conglomerate. 
Some of the shales are calcareous. Intrusive rocks occurring in 
dikes are abundant. These formations are similar to those that 
make up much of the Nutzotin Mountains and are presumably 
Mesozoic in age. 

In view of the presence of auriferous quartz veins in the district 
there can be little doubt as to the source of the placer gold. One such 
mineralized quartz vein, which has long been known, lies close to the 
mouth of Bonanza Creek and therefore near the scene of the first gold 
discovery. The auriferous mineralization is doubtless connected 
with the intrusion of the igneous rocks (p. 312). The gravels that were 
mined in the summer of 1913 will not exceed 4 feet in depth and the 
pay streak on Little Eldorado is reported 1 to be about 100 feet wide. 
These shallow gravels are not moss covered and are therefore not 
permanently frozen. 

During the summer of 1913 the Discovery claim, on Little Eldo¬ 
rado Creek, was opened and was the principal source of the gold 
output of the district. Some mining was also done on near-by claims, 
and placer gold was found on several other creeks in the Chatenda 
and Chapolda basins. 2 The total placer-gold production in 1913 is 
variously estimated, the values given ranging from $30,000 to $70,000. 

Cairnes 3 has described the character of the placer gold as 
follows: 

The gold itself from Chisana that has been assayed is worth about $16.10 per ounce, 
and is dark in color, having a peculiar almost bronzelike cast, due possibly to a 
slight coating of iron oxide. All that has so far been found is also quite coarse, prac¬ 
tically no dust having been obtained. The greater amount of the gold is in particles 
ranging in value from 1 to 10 cents; but nuggets worth from $1 to $2 are common, 
and some have been found worth from $18 to $20, or even more. In shape, the gold 

1 Cairnes, D. P., Chisana gold fields: Canadian Min. Inst. Bull. 24, p. 61,1914. 

2 Recent reports indicate that gold placers have been found on Big Skookam, Dahl, Rhyolite Canyon, 
Gold Run, Big Eldorado, and Dry creeks. A high gold tenor is reported in the gravels at a number of 
new localities, and the outlook for a fairly large gold output in 1914 seems favorable. 

8 Op. cit., p. 62. 




U. S. GEOLOGICAL SURVEY 



SKETCH MAP OF THE CHISANA PLACER DISTRICT. 


















































Ac.-:..' Br'T 10 -JAW HDT3^8 







































































THE CHISANA PLACER DISTRICT. 


317 


particles are dominantly flat, some being decidedly thin and flakelike, indicating 
apparently that the gold was prevailingly deposited originally either in narrow seams 
in the inclosing slate rock or along the contact between quartz veinlets and the 
inclosing rock formations. 

Future of placer mining .—It will be evident that the shallow 
gravels, occupying narrow valley floors, can not contain any large 
amount of auriferous alluvium. The conditions adverse to miningr 
'are lack of timber and, in many of the creeks, scarcity of water, 
conditions that are partly offset by the absence of any overburden 
and the thawed condition of the gravels. The evidence in hand 
indicates that the richer placers can be mined at a profit in spite 
of the present high cost of operating. On the other hand, the dis¬ 
coveries thus far made have not revealed a sufficient bulk of mate¬ 
rial to assure a large placer camp. There are some deep gravels on 
Chapolda, Chatenda, and other creeks of this district, but these have 
not been prospected. Some attempts to reach bedrock during the 
winter of 1912-13 were said to be unsuccessful because flowing water 
was encountered, and if this is common underground mining is not 
likely to be feasible, and any gold in the deep gravels will have to be 
recovered by open cuts. 

There are some gravel-covered benches in this district, said to 
carry gold, but they have not been sufficiently opened up to test 
their value. In its general features this district is comparable to 
the Chistochina, which has produced about $1,700,000 worth of gold 
since mining began, in 1899. 

The evidence in hand indicates that mineralization in the district 
is widespread, and placer prospects have been found both northwest 
and southeast of the scene of the actual mining. Now that the 
prospectors are in this field other discoveries can be expected, and 
there is no reason to believe that auriferous gravels may not occur 
in other parts of the region. 

The fact that the region adjacent to the discovery is glaciated is 
unfavorable for the occurrence of large bodies of workable placers. 
The glaciers have swept away and dissipated nearly all the accumula¬ 
tions of preglacial auriferous gravels, and since the period of glacial 
action the time has not been long enough to permit any large accumu¬ 
lations. Some preglacial channels may, however, be preserved, and 
these would seem to be the best sites for extensive placer deposits. 
The presence or absence of such channels can be established only 
by detailed prospecting. 

The northern fronts of the glaciers that occupied the Chisana 
Valley reached only the north margin of the Tan an a lowland. This 
can therefore be considered the approximate northern limit of 
glaciation, beyond which the preglacial gravels have not been dis¬ 
turbed by ice action. Ice erosion gradually decreased toward the 


318 MINERAL RESOURCES OF ALASKA, 1913. 

limit of glaciation, so that prospectors approaching this area from 
the south should find increasing possibility of discovering undisturbed 
preglacial gravels until they reach the line of the old ice front. 

Another field worthy of investigation for placer gold and adjacent 
to the scene of the discovery is the highlands north of the Tanana 
lowlands. This includes the basins of Scot tie, Gardiner, and other 
creeks flowing from the north. Here, so far as known, the rock for¬ 
mations are in part the same as those of the placer camps of the 
Yukon-Tanana region. Moreover, as already pointed out (p. 314), 
evidence of auriferous mineralization has been observed in this field. 
A few prospectors have roamed over this region, but most of them 
have been without sufficient supplies to permit them to test the 
gravels thoroughly, though colors of gold have been found. The 
gravels in this area are probably deep, how deep no one can foretell. 
It may become necessary to sink prospecting shafts, which in a 
region so remote from transportation routes will be expensive. If 
there are gold deposits here they are probably associated with intru¬ 
sive granites or diorites, as in other parts of the Yukon-Tanana 
region, and the prospector should therefore seek such granite intru- 
sives and, finding them, give special attention to streams that flow 
across the contacts of the igneous rocks and the schists in which 
these rocks have been injected. 

COPPER. 

It is not the purpose of this report to discuss in detail the copper de¬ 
posits of the region, which have been fully described in the publica¬ 
tions already cited. The placer copper of the upper White River has 
long been known and utilized by the natives. It was first visited by 
white men in 1891, when C. W. Hayes, then of the Geological Survey, 
made a brief examination of the occurrence. 1 In 1899 copper was 
first found in bedrock. 2 Since that time many copper-bearing lodes 
have been found and some developments made. No productive 
copper mining can be expected till railroad communication with the 
coast is established. 

The copper occurs (1) in association with ancient volcanics and 
(2) in contact-metamorphic limestones and intrusive diorites. Both 
classes of rocks are typically developed along the northern flank of 
the Wrangell Mountains and are presumably of Carboniferous age. 
The copper-bearing minerals are sulphides and native copper. Native 
copper occurs both as a primary constituent of amygdaloidal lava 
and as a secondary oxidation product of sulphides. 


1 Hayes, C. W., An expedition through the Yukon district: Nat. Geog. Mag., vol. 4, pp. 117-162, 1892. 

2 Brooks A. H., A reconnaissance from Pyramid Harbor to Eagle City, Alaska: U. S. Geol. Survey 
Twenty-first Ann. Rept., pt. 2, pp. 380-381, 1900. 



THE CHISANA PLACER DISTRICT. 


319 


MEANS OF COMMUNICATION. 

The Chisana placer district may be approached by feasible routes 
of travel from nearly every direction. The shortest route from an 
established transportation system leads from McCarthy, a station on 
the Copper River & Northwestern Railway, 191 miles from Cordova, 
over the ice-covered Skolai Pass to White River and thence across a 
second divide to the Chisana. This distance is about 100 miles. The 
journey necessitates crossing the Russell Glacier, a passage involving 
both difficulty and danger. It is available, however, for horses. 
Another route that has been used extends through the Wrangell 
Mountains by way of Nizina and Chisana glaciers. By this route the 
distance from McCarthy to Chisana is about 80 miles. It involves 
crossing glacial ice for some 40 miles, as well as a divide some 11,000 
feet high, and is not available for horses. Glacial ice can be entirely 
avoided by the Valdez or Chitina route, which leaves the railroad at 
Chitina, 131 miles from Cordova, or the coast at Valdez, and follows a 
wagon road to Gulkana, 80 miles from Chitina and 128 miles from 
Valdez. From Gulkana it follows a horse trail to Batzulnetas, near 
the head of Copper River, thence crosses a divide to Nabesna River 
and a second divide to the Chisana. The distance from Gulkana to 
Chisana by this route is about 140 miles, making a total of about 220 
miles to Chitina and 268 miles to Valdez. 

Small steamers have ascended the Tanana as far as the mouth of 
the Nabesna, but navigation is difficult, as the current is swift and 
there are many bars and snags. At low water navigation may not 
be feasible. The mouth of the Nabesna is about 250 miles by river 
from Fairbanks and 70 miles by trail from the Chisana district. The 
old mail trail which leads from Eagle on the Yukon to Tanana Cross¬ 
ing can also be used. By this trail it is about 150 miles to Tanana 
Crossing and thence about 90 miles to the Chisana district. 

There are also two principal routes of access from Canadian ter¬ 
ritory. A wagon road leads from Whitehorse—the end of the rail¬ 
road on the White Pass & Yukon Route, 110 miles from Skagway— 
to Lake Kluane, the distance being 143 miles. Thence there is a 
trail to Chisana by way of White River, the distance being about 225 
miles. The White River route is described by Cairnes 1 as follows: 

The White River route follows up White River from its mouth to Beaver Creek, a 
distance which is generally considered to be about 115 miles but which according to 
a survey of the river made by W. J. Peters in 1898 is only 85 miles. Ordinary light- 
draft steam and gasoline river boats may be navigated for about 60 to 70 miles up 
White River, or to about the mouth of Donjek River; and one small specially designed 
gasoline boat succeeded in reaching the mouth of Beaver Creek [also called Snag 


i Cairnes, D. D., Chisana gold fields: Canadian Min. Inst. Bull. 24, 1914. 





320 MINERAL RESOURCES OF ALASKA, 1913. 

River] and is reported to have made the passage from the mouth of the White to 
Beaver Creek in four days. Poling boats have in the past been mainly utilized on 
White River from the mouth up, and last season were in use especially above the 
mouth of Donjek River, or above the different points at which the power boats were 
inoperative. It is claimed also that it is quite possible to take poling boats a con¬ 
siderable distance up Beaver Creek. 

INDUSTRIAL CONDITIONS. 

The news of the finding of placer gold in the Chisana district was 
quickly disseminated and widely advertised by those who expected 
to reap a profit directly or indirectly from the expected gold seekers. 
It came at a time when placer mining was at a rather low ebb in 
many of the older districts and thus found many who were anxious 
to find a new field of activity. As a consequence several thousand 
gold seekers, both from Alaska and from outside of the Territory, 
started for the scene of discovery, and as the various routes presented 
no serious physical obstacles to travel, most of these reached their 
destination. Many were but ill equipped for a sojourn in a region so 
distant from points of supply and almost at once had to turn back 
for lack of provisions. There was the usual disappointment, for long 
before the main mass of stampeders had reached the new diggings 
every creek in the district had been covered with claim locations. 
The recent change in the placer mining law 7 , how 7 ever, prevented the 
wholesale preemption of the entire district by a few 7 persons, a prac¬ 
tice so frequent under the old statute. 

Nearly 100 cabins were built on lower Chatenda (Johnson) Creek, 
forming “Chisana City,” which became the distributing point for the 
district. It is stated that about 300 men wintered in the district. 
As has already been stated, the gravels do not seem to be favorable 
to underground mining, hence probably no great amount of prospect¬ 
ing was accomplished in the winter. The coming summer will 
undoubtedly witness more thorough prospecting of the know r n placers 
and a further search for other gold-bearing areas. 


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